Implied Volatility Skew (20-Day)

Implied Volatility Skew: A measurement that quantifies the difference in implied volatility of options at lower and higher strike prices.

Prothena Corporation plc (PRTA) had 20-Day Implied Volatility Skew of 0.9821 for 2026-10-16.

Over 300 data fields encompassing historical volatility, implied volatility, and put-call ratios for multiple time frames
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Figures for 2026-10-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4941
Historical Volatility (Parkinson)	0.5549
Implied Volatility (Calls)	0.5737
Implied Volatility (Puts)	0.4802
Implied Volatility (Mean)	0.5269
Put-Call Implied Volatility Ratio	0.8371
Implied Volatility Skew	0.9821
Option Statistics
Put-Call Ratio (Volume)	0.0000
Put-Call Ratio (Open Interest)	0.0056